I'm running a hierarchical multiple regression analysis and from a dataset = containing roughly 5,000 participants. When I run the analysis, due to miss= ing data for some participants, the analysis is done using about 4,000 part= icipants. My query is about how do I obtain descriptive statistics just for the sampl= e of participants who were included in the analysis? Different participants were excluded for different pieces of missing data a= cross 15 predictor variables (some dummy coded), so I can't go through the = data to find each participant with a missing piece of data to individually = exclude them from the descriptive analysis. Thank you for any help!

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8/1/2016 12:10:35 PM

On 01/08/2016 8:10 AM, cosgrag@tcd.ie wrote: > I'm running a hierarchical multiple regression analysis and from a dataset containing roughly 5,000 participants. When I run the analysis, due to missing data for some participants, the analysis is done using about 4,000 participants. > > My query is about how do I obtain descriptive statistics just for the sample of participants who were included in the analysis? > > Different participants were excluded for different pieces of missing data across 15 predictor variables (some dummy coded), so I can't go through the data to find each participant with a missing piece of data to individually exclude them from the descriptive analysis. > > Thank you for any help! > Something like the following ought to do the trick. * Replace Y and X1...XP below with variables in your model. COMPUTE CompleteCase = NMISS(Y,X1,X2,...Xp) = 0. FORMATS CompleteCase (F1). FREQUENCIES CompleteCase. /* Frequency for 1 should = your N. USE ALL. FILTER BY CompleteCase. * Syntax to get descriptive stats here. USE ALL. FILTER OFF. -- Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/Home "When all else fails, RTFM."

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8/1/2016 2:48:58 PM

On Mon, 1 Aug 2016 10:48:58 -0400, Bruce Weaver <bweaver@lakeheadu.ca> wrote: >On 01/08/2016 8:10 AM, cosgrag@tcd.ie wrote: >> I'm running a hierarchical multiple regression analysis and from a dataset containing roughly 5,000 participants. When I run the analysis, due to missing data for some participants, the analysis is done using about 4,000 participants. >> >> My query is about how do I obtain descriptive statistics just for the sample of participants who were included in the analysis? >> >> Different participants were excluded for different pieces of missing data across 15 predictor variables (some dummy coded), so I can't go through the data to find each participant with a missing piece of data to individually exclude them from the descriptive analysis. >> >> Thank you for any help! >> > >Something like the following ought to do the trick. > >* Replace Y and X1...XP below with variables in your model. >COMPUTE CompleteCase = NMISS(Y,X1,X2,...Xp) = 0. >FORMATS CompleteCase (F1). >FREQUENCIES CompleteCase. /* Frequency for 1 should = your N. > >USE ALL. >FILTER BY CompleteCase. >* Syntax to get descriptive stats here. >USE ALL. >FILTER OFF. [Does USE ALL do anything that is not done by "FILTER OFF"?] Assuming that your regression seems to have some value, you should also look at the characteristics of the excluded cases; and (perhaps) contrast the two groups. Do the values for excluded cases support the assumption that the Missing is at-random across cases? If not, you have a problem for drawing inferences. That is why there is a large literature on dealing with Missing in various ways -- using extra dummy variables; schemes to replace missing values; the consequences of dropping variables or cases; whatever. -- Rich Ulrich

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8/1/2016 4:42:14 PM